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Loans - Average Recorded Investment and Interest Recognized on Impaired Loans (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2020
Average Recorded Investment
Total	$ 20,202	$ 20,451
Interest Income
Total	277	436
Real estate loans: | Commercial mortgage
Average Recorded Investment
With No Allowance Recorded	14,522	15,020
With a Related Allowance Recorded	2,335	1,992
Total	16,857	17,012
Interest Income
With No Allowance Recorded	191	286
With a Related Allowance Recorded	41	57
Total	232	343
Real estate loans: | One-to-four family residential mortgage
Average Recorded Investment
With No Allowance Recorded	2,122	2,241
With a Related Allowance Recorded	261	174
Total	2,383	2,415
Interest Income
With No Allowance Recorded	22	51
With a Related Allowance Recorded	5	10
Total	27	61
Real estate loans: | Multifamily
Average Recorded Investment
With No Allowance Recorded	854	915
Total	854	915
Interest Income
With No Allowance Recorded	18	31
Total	18	31
Real estate loans: | Home equity and lines of credit
Average Recorded Investment
With No Allowance Recorded	20	20
With a Related Allowance Recorded	33	33
Total	53	53
Interest Income
With No Allowance Recorded	0	0
With a Related Allowance Recorded	0	1
Total	0	1
Commercial and industrial loans
Average Recorded Investment
With No Allowance Recorded	37	38
With a Related Allowance Recorded	18	18
Total	55	56
Interest Income
With No Allowance Recorded	0	0
With a Related Allowance Recorded	0	0
Total	$ 0	$ 0

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Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

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